Long-Term Tumor-Free Survival in a Patient with Stage IV Epithelial Ovarian Cancer Undergoing High-Dose Chemotherapy and Viscum album Extract Treatment: A Case Report Perm JWerthmann, Paul G.; Kempenich, Robert; Lang-Avérous, Gerlinde; Kienle, Gunver S.March 7, 2021epithelial ovarian cancer, Viscum album extract